Join Brian Lee White for an in-depth discussion in this video Get in the Mix: Using compression to even out a vocal performance, part of Foundations of Audio: Compression and Dynamic Processing.
The human voice, like most acoustic instruments, tends to be very dynamic when recorded. While this enables us to produce a wide variety of sounds from intimate whispers to barbaric shouts, that variety of dynamics can be difficult to fit in to a song's mix. In fact, there aren't many instruments, the human voice included, that are designed specifically to sit in the middle of a huge hundred track pop mix. So they often need a little help to reduce their dynamic range using a compressor. My strategy when it comes to compressing vocals in a mix is pretty simple.
Make the singer sound like a star. This means confident, larger than life vocals that sit in the mix like they were meant to be there. Not strapped on to a background track like a bad night at the Karaoke bar. Now I'm not going to lie. A great sounding vocal track comes from a great vocalist. There isn't any mix magic or super expensive compressor that's going to take that lifeless half-baked vocal track and turn it into the performance of a lifetime. The singer needs to sell the performance during the recording stage. Compressing will only help take a great take and make it sound better.
Let's take a listen to an example, from the song, Say Yes, by Iyeoka. Here's a sample of the lead vocal track without compression. Listen to how some words pop out, while others can't be heard. Now listen to the vocal with compression, and how the level is more consistent. Take a look at the muted track labeled Vocal Processed for a visual representation of what the compressor's doing to the wave form. If you'd like, pause the session and zoom in to take a closer look. An uncompressed vocal often sounds a bit disconnected from the mix. Like it doesn't really belong with the rest of the instruments.
Regardless of the volume level I set the vocal at in the mix, there are bound to be certain words that stick out too far, and others that get buried behind the music bed. I like to think of compression on the vocal as serving two main functions. First, being simple dynamics control, so I can hear what the lyric is saying. And the second being, tonal shaping and firming, so the vocal takes on a larger than life quality and really connects with the listener. Again, listen to the mix and pay attention as I automate the settings to apply compression. And because compression doesn't live in a vacuum, after adjusting the compression, I'll add a little bit of reverb and delay, to sit the vocal into the mix.
Dynamics control of a vocal is a two stage process of tucking in the louder words and phrases and turning up the result, allowing the softer notes to sit at or near the level of the louder ones. This is achieved by pulling down threshold until the louder words start to trigger compression, about 60 dbs on average of gain reduction in this case. And then making up the loss in signal level using the output gain. Notice that I am using a ratio of about six to one, an attack of 10 milliseconds in a release time that allows the compressor to recover between words.
I am also using a softnee setting to help the compressor ease into the ratio and sound more transparent. Once I have the vocals sitting in the mix using compression, I will then consider adding volume automation to perfect the balance over each section and fine tune any trouble spots that still stick out or fall below the mix. As I listen to and adjust other tracks, I may come back to the vocal and adjust some of the settings to increase or decrease the total amount of gain reduction. Or try a different compressor depending on how the mix is shaping out. This same technique works for almost any instrument in your mix.
Once you determine that a track needs a bit of compression, start small and work your way into the sweet spot. Throughout this course, I'll tend to process audio examples a bit more aggressively for greater educational impact. You generally want to avoid over-compressing the signal, unless that's the effect you're going for.
- Measuring amplitude
- Understanding dynamic range
- Introducing compressors
- Utilizing compression ratios
- Applying attack and release
- Evening out a vocal performance with compression
- Adding punch and sustain to drums
- Using compression presets intelligently
- How to record with compression
- Solving common mix problems with limiters
- De-essing a vocal track
- Using gates and expanders
- Controlling frequency content with multiband compressors
- Using sidechains creatively
- Keying gates and compressors
- Fixing overcompressed tracks
- Using mixbus compression
- Working with parallel compression
- Compression and limiting best practices